CLASS III CRINOIDEA 173 



Class 3. CRINOIDEA Miller. Sea-lilies. ' 

 (Brachiata Bronn ; Adinoidea F. Roemer.) 



Usually long-stalked, more rarely non-pedunculate and sessile, frequently free- 

 swimming Pclmatozoa, with calyx composed of regularly arranged plates, and provided 

 with iveU-developed movable arms. 



The Crinoid organism, consists of three principal elements — calyx, arms 

 and stalk. The calyx and arms together are sometimes spoken of as the 

 crown, as contrasted with the column (also called stem or stalk). 



1. The Cahjx. — The calyx has usually the form of a cup-shaped, bowl- 

 shaped, or globular capsule, within which the more important organs are 

 enclosed. Its lower (dorsal or abactinal) surface commonly I'ests upon a 

 column (Fig. 267); but in some forms it is attached directly by the base, 

 and in rare instances it is free. The superior (ventral or actinal) surface is 

 either membranous or plated ; it carries the mouth and ambulacral grooves, 

 and hence is homologous with the under side of a star-fish or sea-urchin. As 

 a rule, only the inferior and lateral portions {dorsal cup) of the calyx are 

 visible, owing to the concealment of the summit by the arms. The cup 

 is constituted of two or more circlets of plates, which are uniformly oriented 

 with reference to the ambulacral organs. 



a. By the base is understood the one or two circlets of plates intervening 

 between the topmost joint of the column and the first cycle of radially situated 



1 Literature : Miller, J. S., A Natural History of the Crinoidea or lily-shaped Animals, 1821. — 

 Mailer, J., Ueber den Ban des Pentacrinus caput-viedusae. Abhandl. Akad. Wiss. Berlin, 1841. 

 — de Koninck, L. Q., et le Hon. H., Recherches siir les crinoides du terrain carbonifcre de la Bel- 

 gique. Brussels, 1854. (Very extensive bibliography.)— iJcyric/!-, E., Die Criuoideen des Muschel- 

 kalks. Abhandl. Akad. Wiss. Berlin, 1857. — Schultze, L., Monographie der Echinodermen des 

 Eifler Kalks. Denkschrift Akad. Wiss., 1867, vol. xx\i.—Shumarcl, B. F., Catalogue of Palaeozoic 

 Echinodermata of North America. Trans. St. Louis Acad. Sci., 1868, vol. ii. (Very complete 

 bibliography.) — Carpenter, W. B., On the Structure, Physiology, and Development of Antedon 

 rosaceus. Philos. Trans., 1876, vol. clvi. — Wachsmuth, C, and Springer, F., Revision of the Palaeo- 

 crinoidea. l.-lll. Proc. Acad. Nat. Sci. Philad., 1879-86. — Idem, Discovery of the Ventral Struc- 

 ture of Taxocrinus and Haplocrinus, ibid., 188S.— Idem, The Perisomic Plates of Crinoids, ibid., 1890. 

 ■ — Idem, The Crinoidea Camerata of North America. Mem. Mus. Comp. Zool.,1897, vols, xx., xxi. 

 — Loriol, P. de, Paleontologie Fran9aise. Crinoides Jurassiques, I. -II., 1882-89. — JS'eiimayr, M., 

 Die Stiimme des Tierreichs, 1889. — Agassiz,A., Calamocrinus Diomedae. Memoirs Museum Comp. 

 Zool. 1892, vol. xvii. — Bather, F. A., British Fossil Crinoids. Ann. and Mag. Nat. Hist., 1890-92, 

 ser. 6, vols, v.-ix. — Ide7)i, The Crinoidea of Gotland. K. Svenska Vetensk. Akad. Handlingar, 

 1893, vol. XXV. — Idem, A Treatise ou Zoology (Lankester) pt. iii., Echinoderma, 1900. — Jacket, 

 0., Criuoiden Deutschlands. Pal. Abhandl. Jena, neue Folge, 1895, vol. iii. — Springer, F., Uiuta- 

 crinus, its structure and relations. Mem. Mus. Comp. Zool., 1901, vol. xxv.. No. 1. — Idem, Cleio- 

 crinus. Mem. Mus. Comp. Zool., 1905, vol. xxv., No. 2. — Idem, Discovery of the disk of 

 Ouychocrinns. Journ. Geol., 1906, vol. xiv. — Idem, A Trenton Echinoderm Fauna. Geol. Surv. 

 Canada, 1911, Memoir No. 15, P. — Idem, New American Fossil Crinoids. Mem. Mus. Comp. Zool., 

 1911, vol. XXV., No. 3. — Idem,, The Crinoidea Flexibilia. (Mouogiaph in preparation.) — Cliad- 

 ivick, H. €., Antedon. Liverpool Marine Biol. Coram., 1907, Mem. 15.- — Clark, A. II., Variou.« im- 

 portant papers on recent and fossil Crinoids in Proc. U.S. Nat. Mus., 1908-11, vols, .xxxiv. -xl. — 

 Idem, On a collection of Crinoids from the Zoological Museum of Copenhagen. Vidensk, Medd. 

 fra den Naturhist. Forening i. K0benhavn, 1909. — The probable origin of the Crinoidal nervous 

 system. Amer. Nat. 1910, vol. xliv. — Remarks on the nervous system and symmetry of the 

 Crinoids. Journ. Wash. Acad. Sci., 1911, vol. i. — The Recent Crinoids of Australia. Memoir 4, 

 Australian Museum, Sydney, N.S.W., 1911.— The Crinoids of tlie Indian Ocean. Memoir of the 

 Indian Museum, Calcutta. (In press.) — The Existing Crinoids. Special Bulletin, U.S. National 

 Museum. (In press.) — Wood, E., A critical summary of Troost's unpublished manuscript on the 

 Crinoids of Tennessee. Bull. U.S. Nat. Mus., 1909, No. 64. — Kirk, E., Structure and relationships 

 of certain Eleutherozoic Pelmatozoa. Proc. U.S. Nat. Mus., 1911, vol. xli. 



